text: // Copyright 2019 The gVisor Authors.
  //
  // Licensed under the Apache License, Version 2.0 (the "License");
  // you may not use this file except in compliance with the License.
  // You may obtain a copy of the License at
  //
  //     http://www.apache.org/licenses/LICENSE-2.0
  //
  // Unless required by applicable law or agreed to in writing, software
  // distributed under the License is distributed on an "AS IS" BASIS,
  // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  // See the License for the specific language governing permissions and
  // limitations under the License.
  
  #include <errno.h>
  #include <stdlib.h>
  #include <sys/socket.h>
  #include <sys/types.h>
  #include <sys/un.h>
  
  #include <string>
  #include <tuple>
  
  #include "gtest/gtest.h"
  #include "test/util/file_descriptor.h"
  #include "test/util/fs_util.h"
  #include "test/util/socket_util.h"
  #include "test/util/test_util.h"
  
  // This file contains tests specific to connecting to host UDS managed outside
  // the sandbox / test.
  //
  // A set of ultity sockets will be created externally in $TEST_UDS_TREE and
  // $TEST_UDS_ATTACH_TREE for these tests to interact with.
  
  namespace gvisor {
  namespace testing {
  
  namespace {
  
  struct ProtocolSocket {
    int protocol;
    std::string name;
  };
  
  // Parameter is (socket root dir, ProtocolSocket).
  using GoferStreamSeqpacketTest =
      ::testing::TestWithParam<std::tuple<std::string, ProtocolSocket>>;
  
  // Connect to a socket and verify that write/read work.
  //
  // An "echo" socket doesn't work for dgram sockets because our socket is
  // unnamed. The server thus has no way to reply to us.
  TEST_P(GoferStreamSeqpacketTest, Echo) {
    std::string env;
    ProtocolSocket proto;
    std::tie(env, proto) = GetParam();
  
    char* val = getenv(env.c_str());
    ASSERT_NE(val, nullptr);
    std::string root(val);
  
    FileDescriptor sock =
        ASSERT_NO_ERRNO_AND_VALUE(Socket(AF_UNIX, proto.protocol, 0));
  
    std::string socket_path = JoinPath(root, proto.name, "echo");
  
    struct sockaddr_un addr = {};
    addr.sun_family = AF_UNIX;
    memcpy(addr.sun_path, socket_path.c_str(), socket_path.length());
  
    ASSERT_THAT(connect(sock.get(), reinterpret_cast<struct sockaddr*>(&addr),
                        sizeof(addr)),
                SyscallSucceeds());
  
    constexpr int kBufferSize = 64;
    char send_buffer[kBufferSize];
    memset(send_buffer, 'a', sizeof(send_buffer));
  
    ASSERT_THAT(WriteFd(sock.get(), send_buffer, sizeof(send_buffer)),
                SyscallSucceedsWithValue(sizeof(send_buffer)));
  
    char recv_buffer[kBufferSize];
    ASSERT_THAT(ReadFd(sock.get(), recv_buffer, sizeof(recv_buffer)),
                SyscallSucceedsWithValue(sizeof(recv_buffer)));
    ASSERT_EQ(0, memcmp(send_buffer, recv_buffer, sizeof(send_buffer)));
  }
  
  // It is not possible to connect to a bound but non-listening socket.
  TEST_P(GoferStreamSeqpacketTest, NonListening) {
    std::string env;
    ProtocolSocket proto;
    std::tie(env, proto) = GetParam();
  
    char* val = getenv(env.c_str());
    ASSERT_NE(val, nullptr);
    std::string root(val);
  
    FileDescriptor sock =
        ASSERT_NO_ERRNO_AND_VALUE(Socket(AF_UNIX, proto.protocol, 0));
  
    std::string socket_path = JoinPath(root, proto.name, "nonlistening");
  
    struct sockaddr_un addr = {};
    addr.sun_family = AF_UNIX;
    memcpy(addr.sun_path, socket_path.c_str(), socket_path.length());
  
    ASSERT_THAT(connect(sock.get(), reinterpret_cast<struct sockaddr*>(&addr),
                        sizeof(addr)),
                SyscallFailsWithErrno(ECONNREFUSED));
  }
  
  // Bind to a socket, then Listen and Accept.
  TEST_P(GoferStreamSeqpacketTest, BindListenAccept) {
    // Binding to host socket requires LisaFS.
    SKIP_IF(!IsLisafsEnabled());
  
    std::string env;
    ProtocolSocket proto;
    std::tie(env, proto) = GetParam();
  
    char* val = getenv(env.c_str());
    ASSERT_NE(val, nullptr);
    std::string root(val);
  
    FileDescriptor sock =
        ASSERT_NO_ERRNO_AND_VALUE(Socket(AF_UNIX, proto.protocol, 0));
  
    std::string socket_path =
        JoinPath("/tmp/sockets", proto.name, "created-in-sandbox");
  
    struct sockaddr_un addr = {};
    addr.sun_family = AF_UNIX;
    memcpy(addr.sun_path, socket_path.c_str(), socket_path.length());
  
    ASSERT_THAT(
        bind(sock.get(), reinterpret_cast<struct sockaddr*>(&addr), sizeof(addr)),
        SyscallSucceeds());
  
    ASSERT_THAT(listen(sock.get(), 1), SyscallSucceeds());
  
    FileDescriptor accSock =
        ASSERT_NO_ERRNO_AND_VALUE(Accept(sock.get(), NULL, NULL));
  
    // Other socket should be echo server.
    constexpr int kBufferSize = 64;
    char send_buffer[kBufferSize];
    memset(send_buffer, 'a', sizeof(send_buffer));
  
    ASSERT_THAT(WriteFd(accSock.get(), send_buffer, sizeof(send_buffer)),
                SyscallSucceedsWithValue(sizeof(send_buffer)));
  
    char recv_buffer[kBufferSize];
    ASSERT_THAT(ReadFd(accSock.get(), recv_buffer, sizeof(recv_buffer)),
                SyscallSucceedsWithValue(sizeof(recv_buffer)));
    ASSERT_EQ(0, memcmp(send_buffer, recv_buffer, sizeof(send_buffer)));
  }
  
  INSTANTIATE_TEST_SUITE_P(
      StreamSeqpacket, GoferStreamSeqpacketTest,
      ::testing::Combine(
          // Test access via standard path and attach point.
          ::testing::Values("TEST_UDS_TREE", "TEST_UDS_ATTACH_TREE"),
          ::testing::Values(ProtocolSocket{SOCK_STREAM, "stream"},
                            ProtocolSocket{SOCK_SEQPACKET, "seqpacket"})));
  
  // Parameter is socket root dir.
  using GoferDgramTest = ::testing::TestWithParam<std::string>;
  
  // Connect to a socket and verify that write works.
  //
  // An "echo" socket doesn't work for dgram sockets because our socket is
  // unnamed. The server thus has no way to reply to us.
  TEST_P(GoferDgramTest, Null) {
    std::string env = GetParam();
    char* val = getenv(env.c_str());
    ASSERT_NE(val, nullptr);
    std::string root(val);
  
    FileDescriptor sock =
        ASSERT_NO_ERRNO_AND_VALUE(Socket(AF_UNIX, SOCK_DGRAM, 0));
  
    std::string socket_path = JoinPath(root, "dgram/null");
  
    struct sockaddr_un addr = {};
    addr.sun_family = AF_UNIX;
    memcpy(addr.sun_path, socket_path.c_str(), socket_path.length());
  
    ASSERT_THAT(connect(sock.get(), reinterpret_cast<struct sockaddr*>(&addr),
                        sizeof(addr)),
                SyscallSucceeds());
  
    constexpr int kBufferSize = 64;
    char send_buffer[kBufferSize];
    memset(send_buffer, 'a', sizeof(send_buffer));
  
    ASSERT_THAT(WriteFd(sock.get(), send_buffer, sizeof(send_buffer)),
                SyscallSucceedsWithValue(sizeof(send_buffer)));
  }
  
  INSTANTIATE_TEST_SUITE_P(Dgram, GoferDgramTest,
                           // Test access via standard path and attach point.
                           ::testing::Values("TEST_UDS_TREE",
                                             "TEST_UDS_ATTACH_TREE"));
  
  }  // namespace
  
  }  // namespace testing
  }  // namespace gvisor
  